1. Field of the Invention
The present invention relates to power dividers. More specifically, the present invention relates to microwave power dividers.
While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, and embodiments within the scope thereof and additional fields in which the present invention would be of significant utility.
2. Description of the Related Art
Power dividers are known and used widely in the art to divide power in an input path into two or more output paths. When energy flows in an opposite direction through a power divider, the power divider acts as a power combiner.
Cascaded power dividers are particularly well known in the art. A simple conventional power divider splits input power between two output paths. It is therefore regarded as a 2:1 power divider. Where more than two outputs are desired, the simple power dividers are cascaded end-to-end. For example, where it is desired to provide a four-way division of input power, three simple 2:1 conventional power dividers are cascaded. Two of the power dividers are input connected to the third divider at the outputs thereof.
As the length of the power dividers is determined with regard to the need to match the impedance and/or other electrical characteristics of a transmission line, the cascading of power dividers often results in a power divider which is relatively long. The length of a power divider is directly related to its loss and may impose space constraints on a host system.
Single junction power dividers do not generally suffer the length problems of cascaded designs. Single junction power dividers include several taps from a single junction. While the taps are generally small in width at the junction, the taps include a section which has a discrete increase in width for impedance matching purposes. Because of the discrete step change in width, single junction power dividers are characterized by a rather limited passband. See "A Broadband Planar N-Way Combiner/Divider" published in IEEE MTT-S on June 1977 by Z. Galani and S. J. Temple, pp. 499-502.
A paper entitled "A New N-Way Broadband Planar Power Combiner/Divider", published in Microwave Journal on November 1986 by W. Yau, J. M. Schellenberg, and Y. C. Shih pp. 147-150 appears to disclose a single junction power combiner/divider utilizing a tapered transmission line. However, this device is not a power divider, per se, as power is divided internally, amplified and combined at a single junction prior to being output. Also, even if the device is modified to provide a power divider, the individual transmission lines in the device are probably too close electrically to avoid impedance matching problems. In addition, the size of the device would be such that it would be somewhat difficult to make attachments at the outputs thereof.
Thus, there is a need in the art for a compact, broadband, highpass, high efficiency microwave power divider.